Metal cutting knife



March 17, 1953 F. FOURNIER METAL CUTTING KNIFE Filed Dec. 9, 1950 firzn/o t' ja /1 4043 001 12542 Patented Mar. 17, 1953 METAL CUTTING KNIFE Francois Fournier, Montreal, Quebec, Canada Application December 9, 1950, Serial No. 199,947 In Canada February 11, 1950 1 Claim.

The present invention pertains to a novel knife for cutting sheet metal such as automobile fenders and other body parts. This operation is performed in removing a rusted or defective area of metal to replace it with a matching piece welded in the hole.

Present cutters, such as shears, leave a bent or ragged edge on the metal. This edge must be trimmed before the new piece can be applied. The principal object of the present invention is to provide a cutter that leaves a clean edge ini-- tially. This result is accomplished by means of a tool which, in cutting, removes a thin strip of metal rather than merely bending the displaced metal out of the original plane.

A further object of the invention is to rovide a handle capable of holding the blade in a number of angular positions, according to the requirements of the job. Still another object of the invention is to provide an extremely simple and inexpensive construction for the purposes set forth.

In the accomplishment of these objects there is provided a somewhat elongated fiat blade sharpened at both its surfaces along one or more edges. At one or both ends of such doublesharpened edge or edges, sharp prongs are extended outwardly. The sharpened edge is shaped concavely immediately adjacent to each prong.

The prong is inserted where the metal is to be cut, and the blade is forced along the metal by pressure. In this movement the blade removes a narrow strip of metal that curls in the concavity. An area of metal is eventually evered, and the opening thus formed has a clean edge as a result of the removal of the curl in the advance movement of the blade.

The invention is fully disclosed by way of example in the following description and in the accompanying drawings in which:

Figure 1 is a perspective view of the device;

Figure 2 is a plan view showing the work in section;

Figure 3 is a similar plan view showing the blade in a different adjustment;

Figure 4 is a perspective view of the blade;

Figure 5 is an end view;

Figure 6 is a perspective view of the clamping plate, and

Figure 7 is a section on the line 11 of Figure 8.

Reference to these views will now be made by use of like characters which are employed to designate corresponding parts throughout.

In Figure 1 is shown an elongated metal plate I that constitutes the handle of the knife. One end has a pair of apertures 3 and covers a shorter or clamping plate 4 that is similarly apertured at 5 to coincide with the apertures 3. A blade 6 is inserted between the plates and is secured by tightening bolts I passed through the registering apertures, by means of nuts 8.

The blade 6 is a somewhat elongated or striplike member of a hard metal. Both ends of the strip are shouldered laterally at the corners to form outwardly extending prongs 9. Beneath the prongs, the longitudinal edges of the blade are rounded inwardly or concavely at [0, for a purpose that will presently be described. The edges of the blade are suitably sharpened at both surfaces.

In use, the blade is inserted between the plates I and 4 and secured therein by the means previously described. It is also set between the bolts 1 at the desired angle and in engagement therewith, so that it does not swivel under working pressure. The angle best suited for the particular job is selected, and considerable versatility in the use of the tool is possible by the angular relation of the blade to the handle.

In cutting sheet metal such as automobile fenders and body parts, the cut is started by first piercing the metal H with one of the prongs 9. Thereafter, as the blade is drawn through the metal, it removes a shaving or curl l2. The tool is advanced by tapping on the forward end of plate I, in the direction shown by the arrow in Figure 3. The curl rolls up in the concavity In.

The distinctive feature of the blade is that, in removing metal, it forms a clean cut with no ragged edge. Conventional cutters, on the other hand, leave a bent or twisted edge that must be trimmed.

After a defective or damaged area of metal has been removed, it may be replaced by an equivalent piece welded in the opening.

Although a specific embodiment of the invention has been illustrated and described, it will be understood that various alterations in the details of construction may be made without departing from the scope of the invention as indicated by the appended claim.

What I claim is:

A. knife comprising a flat blade sharpened along opposite edges at both surfaces, a prong extending outwardly from each edge at both ends of said blade, said edges being concave immedi ately adjacent to said prongs, a handle plate and a clamp late engaging opposite surfaces of said blade and lying parallel to said surfaces, a pair of bolt extending through registering apertures file of this patent:

UNITED STATES PATENTS Name Date Cushman June 22, 1875 Erickson Nov. 17, 1925 Tobin Sept. 6, 1932 Poe Mar. 30, 1937 Rich Dec. 27, 1938 FOREIGN PATENTS Country Date Germany June 3, 1932 

